Well in theory since it seeks to criminalize what is currently civil copyright infringement and thus far is purposefully vague as to give authorities and copyright holders a lot of room to work with against people who infringe on copyrights. Fan art and fan fiction, regardless of whether or not there is a disclaimer, infringes on copyright. As it is many copyright holders don't care that much about free fan fiction and fan art, in fact some encourage it since they feel it's good for business, but some are very much opposed to it, especially fan fiction and fan art of an erotic nature, but luckily they don't bother most of the time since current laws make it a civil matter and since it's free the most they could get out of a law suit is the removal of the content. Under the acta laws governing the handling of copyright infringement change. One of the main tools of the acta is giving authorities the ability to go after people without permission from copyright holders and takes away ISP's safe harbor status forcing them to comply with any request for information regardless of whether or not they have a warrant. So if it were to pass it could potentially spell a bit of trouble not just for ff writers but more so for anyone who downloads anything at sources other than directly from copyright holders.
However, as DemonGoddess061 pointed out, it's still being hammered out and might stay that way for a while. In the end it may turn out drastically different than it currently is and hopefully may wind up being implemented very differently than my paranoid mind says it may. Hell, it might even not get passed at all.
Still people should keep an eye on it. some of the stuff proposed in it is down right awful (such as ipod checks for copied music at customs and border crossings, though I'm not sure if that part got shot down yet) and how it's even made it this far is people are being kept in the dark about what's being done. It wasn't my intent to scare anyone and I'm truly sorry if I have but I felt it was a matter too important not to bring up.
P.S. thank you to Demongoddess061 for answering my query in a timely and thorough manner and for all the tremendous hard work you put into this site. and for putting up with a paranoid idiot like me